GM stops Volt production for 5 weeks

General Motors is temporarily halting production of the Chevrolet Volt due to slack sales.

NEW YORK (CNNMoney) -- President Barack Obama said recently he'd buy a Chevrolet Volt after he left office "in five more years."

It seems like General Motors could use that business much sooner. The automaker said Friday it is halting the Detroit production line for the Chevrolet Volt for five weeks as it works to sell down its existing inventory of the plug-in car.

Last month, Volt sales actually rose substantially compared to the prior months. Chevrolet dealers sold 1,023 of the cars in February compared to only 600 in January.

Still, GM (GM, Fortune 500) has more Volts sitting on dealer lots than it has buyers. GM had, in the past, said slow sales were the result of an insufficient supply of cars, not a lack of demand. Now, the carmaker is admitting that supply is no longer the problem.

The automaker had recently launched a new marketing campaign to boost the car's image following a National Highway Traffic Safety Administration investigation into possible battery fires. That investigation closed last month after the agency determined there was no greater risk of fire in the Volt than in any ordinary gasoline-powered car.

During the investigation, GM offered to lend other cars to Volt owners who might be concerned about their safety and even offered to buy back the cars.

Besides Volts for sale in the U.S., the Detroit factory also produces a versions of the car for Europe where it sells with a somewhat different design as the Opel Ampera.

It is not unusual for automakers to temporarily shut down factories when inventories of certain models get backed up. The Volt, however, has been a halo vehicle for GM and, compared to more mainstream cars, sales goals for it were relatively modest.